Non-aqueous solutions of hydrogen peroxide in various organic solvents as is known are employed in many reactions, e.g. oxidations, epoxidations or in nuclear (ring) hydroxylation of phenols. Since the presence of water has a disturbing influence on the reactions mentioned, there have already been attempts to obtain organic solutions of hydrogen peroxide which have as low a water content as possible, see Organic Reactions, Vol. 7, page 395 (1953); German Pat. No. 2038319, German Pat. No. 2038320, German AS No. 2410742, German AS No. 2462957, and German AS No. 2462990.
However, difficulties appeared in the production of these types of solutions since the water content of the solutions was too high and besides there occurred a significant loss of hydrogen peroxide by entrainment during the distillation of water and through decomposition in the sump,, see German Pat. Nos. 2038319 and 2038320.
If phenol wherein phenol is phenol per se or its derivatives are used as solvent then hydrogen peroxide, which already is present in an organic solvent having a boiling point above phenol or its derivatives and above hydrogen peroxide, would distill off together with phenol or its derivatives from the high boiling solvent.
Thus it is known according to German AS No. 2462957 to produce a solution of hydrogen peroxide in phenol in the manner that there is added in a column to phenol which is distilling overhead a solution of hydrogen peroxide in a high boiling solvent such as an ester of phosphoric acid,, e.g. in triisooctyl phosphate, which solution has a low water content, and to distill off the overhead in a vacuum at a head temperature of about 75.degree. C., the phenol together with the hydrogen peroxide. Hereby the entire amount of hydrogen peroxide goes over with the phenol. There is described in German AS No. 2462990 a corresponding process for phenol derivatives.
Thus there is a two-step process for the production of the desired solution,, namely the product of a hydrogen peroxide solution in an ester of phosphoric acid, and then the conversion of this solution into a solution of hydrogen peroxide in phenol.
Additionally in the second step the hydrogen peroxide must be completely distilled off and therefore it is present for a long time at elevated temperature. Through this there is not only the danger of decomposition and therewith a loss of hydrogen peroxide but in this total vaporization there are formed additional sensitive gas mixtures which contain the hydrogen peroxide in vapor form.